1. Field of the Invention
The present invention relates generally to sheet handling systems, and in particular to a system and method for directing sheets into specific sheet receiving stations without using active gates, moving the stations or moving/translating the entrance nip.
2. Prior Art
There are three primary paper-handling schemes used in sorters and Mailbox devices. One method is to use fixed stations and a series of gates that are actuated by a series of solenoids, or some other active means. Very often these systems have a separate solenoid for each gate. A second scheme uses fixed stations and a moving entrance nip to deliver the sheet to the appropriate station. In this type of system a xe2x80x9cwindow shadexe2x80x9d type system holds sheets to the belt. This type of system can cause problems with high static. Also, these systems often include an eject nip that is driven up and down with a separate drive system in order to deliver the sheet to the appropriate station. A third scheme uses moving stations that increment up and down past a fixed sheet ejection nip system. Generally, a mechanism is required to lift/move the entire station array as well as each separate station at the paper entrance for loading. All three of these schemes require a significant number of moving parts and control electronics. Furthermore, a moving station scheme is not very desirable for a Mailbox system since the stations are unloaded on an ongoing basis (not just at the end of a job like in a copier), and having moving stations can create operability and safety issues.
The present invention is directed to an improved sheet handling and transporting apparatus and method. In one embodiment of the invention, the apparatus comprises a sheet transport mechanism adapted to move a sheet in a first direction along a path in the apparatus, and a plurality of sheet receiving stations. The apparatus includes a gate associated with a each station. The transport mechanism is adapted to deliver the sheet into a selected station by reversing the direction of the sheet in the path when the sheet is at a point adjacent a gate corresponding to the selected station.
The present invention, in another embodiment, is directed to a method of directing a sheet into a sheet receiving station of a transport apparatus. The method comprises transporting the sheet in a first direction in the apparatus and stopping the sheet at a point adjacent a gate associated with the sheet receiving station. The sheet is then transported in a second direction and directed into the sheet receiving station through a gate.
In another aspect, the present invention, in another embodiment, is directed to a method of directing a sheet into one of a plurality of sheet receiving stations in a reversible drive transport apparatus. The method comprises detecting a presence of a sheet in a first transport path of the transport apparatus. The sheet is transported in a first direction along the first transport path for a predetermined time period after being detected that is associated with a selected sheet-receiving station. The direction of the sheet is reversed and the sheet is directed into a second transport path using a passive gate associated with the selected station and delivered into the selected station.
In a further embodiment, the present invention is directed to a method of directing a sheet into a bin of a sheet sorter apparatus. The method comprises receiving the sheet into the sheet sorter apparatus and determining if a time gap is required between the sheet and another sheet. The sheet is detected in a path of the apparatus and a sorter drive timing sequence is initiated. The timing sequence is adapted to stop a drive of the apparatus after a predetermined time associated with the bin. The drive of the sorter apparatus is then reversed to drive the sheet into the bin.